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1.
Int J Pharm ; 661: 124420, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971512

RESUMO

Colorectal cancer represents a worldwide spread type of cancer and it is regarded as one of the leading death causes, along with lung, breast, and prostate cancers. Since conventional surgical resection and chemotherapy proved limited efficiency, the use of alternative drug delivery systems that ensure the controlled release of cytostatic agents possess immense potential for treatment. In this regard, the present study aimed to develop and evaluate the efficiency of a series of irinotecan-loaded magnetite-silica core-shell systems. The magnetite particles were obtained through a solvothermal treatment, while the silica shell was obtained through the Stöber method directly onto the surface of magnetite particles. Subsequently, the core-shell systems were physico-chemically and morpho-structurally evaluated trough X-ray diffraction (XRD) and (high-resolution) transmission electron microscopy ((HR-)TEM) equipped with a High Annular Angular Dark Field Detector (HAADF) for elemental mapping. After the irinotecan loading, the drug delivery systems were evaluated through Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry and differential scanning calorimetry (TG-DSC), and UV-Vis spectrophotometry. Additionally, the Brunauer-Emmett-Teller (BET) method was employed for determining the surface area and pore volume of the systems. The biological functionality of the core-shells was investigated through the MTT assay performed on both normal and cancer cells. The results of the study confirmed the formation of highly crystalline magnetite particles comprising the core and mesoporous silica layers of sizes varying between 2 and 7 nm as the shell. Additionally, the drug loading and release was dependent on the type of the silica synthesis procedure, since the lack of hexadecyltrimethylammonium bromide (CTAB) resulted in higher drug loading but lower cumulative release. Moreover, the nanostructured systems demonstrated a targeted efficiency towards HT-29 colorectal adenocarcinoma cells, as in the case of normal L929 fibroblast cells, the cell viability was higher than for the pristine drug. In this manner, this study provides the means and procedures for developing drug delivery systems with applicability in the treatment of cancer.

2.
Nanomaterials (Basel) ; 14(14)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39057873

RESUMO

This review covers recent compositions of bioactive glass, with a specific emphasis on both inorganic and organic materials commonly utilized as matrices for injectable materials. The major objective is to highlight the predominant bioactive glass formulations and their clinical applications in the biomedical field. Previous studies have highlighted the growing interest among researchers in bioactive glasses, acknowledging their potential to yield promising outcomes in this field. As a result of this increased interest, investigations into bioactive glass have prompted the creation of composite materials and, notably, the development of injectable composites as a minimally invasive method for administering the material within the human body. Injectable materials have emerged as a promising avenue to mitigate various challenges. They offer several advantages, including minimizing invasive surgical procedures, reducing patient discomfort, lowering the risk of postoperative infection and decreasing treatment expenses. Additionally, injectable materials facilitate uniform distribution, allowing for the filling of defects of any shape.

3.
Int J Mol Sci ; 25(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38892267

RESUMO

Food safety and quality are major concerns in the food industry. Despite numerous studies, polyethylene remains one of the most used materials for packaging due to industry reluctance to invest in new technologies and equipment. Therefore, modifications to the current materials are easier to implement than adopting whole new solutions. Antibacterial activity can be induced in low-density polyethylene films only by adding antimicrobial agents. ZnO nanoparticles are well known for their strong antimicrobial activity, coupled with low toxicity and UV shielding capability. These characteristics recommend ZnO for the food industry. By incorporating such safe and dependable antimicrobial agents in the polyethylene matrix, we have obtained composite films able to inhibit microorganisms' growth that can be used as packaging materials. Here we report the obtaining of highly homogenous composite films with up to 5% ZnO by a melt mixing process at 150 °C for 10 min. The composite films present good transparency in the visible domain, permitting consumers to visualize the food, but have good UV barrier properties. The composite films exhibit good antimicrobial and antibiofilm activity from the lowest ZnO composition (1%), against both Gram-positive and Gram-negative bacterial strains. The homogenous dispersion of ZnO nanoparticles into the polyethylene matrix was assessed by Fourier transform infrared microscopy and scanning electron microscopy. The optimal mechanical barrier properties were obtained for composition with 3% ZnO. The thermal analysis indicates that the addition of ZnO nanoparticles has increased thermal stability by more than 100 °C. The UV-Vis spectra indicate a low transmittance in the UV domain, lower than 5%, making the films suitable for blocking photo-oxidation processes. The obtained films proved to be efficient packaging films, successfully preserving plum (Rome) tomatoes for up to 14 days.


Assuntos
Embalagem de Alimentos , Polietileno , Solanum lycopersicum , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Embalagem de Alimentos/métodos , Polietileno/química , Solanum lycopersicum/microbiologia , Antibacterianos/farmacologia , Antibacterianos/química , Testes de Sensibilidade Microbiana , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Biofilmes/efeitos dos fármacos
4.
Pharmaceutics ; 16(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38675186

RESUMO

Melissa officinalis is an important medicinal plant that is used and studied intensively due to its numerous pharmacological effects. This plant has numerous active compounds with biomedical potential; some are volatile, while others are sensitive to heat or oxygen. Therefore, to increase stability and prolong biological activities, the natural extract can be loaded into various nanostructured systems. In this study, different loading systems were obtained from mesoporous silica, like Mobile Composition of Matter family (MCM) with a hexagonal (MCM-41) or cubic (MCM-48) pore structure, simple or functionalized with amino groups (using 3-aminopropyl) such as triethoxysilane (APTES). Thus, the four materials were characterized from morphological and structural points of view by scanning electron microscopy, a BET analysis with adsorption-desorption isotherms, Fourier-transform infrared spectroscopy (FTIR) and a thermogravimetric analysis coupled with differential scanning calorimetry. Natural extract from Melissa officinalis was concentrated and analyzed by High-Performance Liquid Chromatography to identify the polyphenolic compounds. The obtained materials were tested against Gram-negative bacteria and yeasts and against both reference strains and clinical strains belonging to Gram-positive bacteria that were previously isolated from intra-hospital infections. The highest antimicrobial efficiency was found against Gram-positive and fungal strains. Good activity was also recorded against methicillin-resistant S. aureus, the Melissa officinalis extract inhibiting the production of various virulence factors.

5.
Molecules ; 29(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675662

RESUMO

Membrane materials with osmium nanoparticles have been recently reported for bulk membranes and supported composite membrane systems. In the present paper, a catalytic material based on osmium dispersed in n-decanol (nD) or n-dodecanol (nDD) is presented, which also works as an emulsion membrane. The hydrogenation of p-nitrophenol (PNP) is carried out in a reaction and separation column in which an emulsion in the acid-receiving phase is dispersed in an osmium nanodispersion in n-alcohols. The variables of the PNP conversion process and p-aminophenol (PAP) transport are as follows: the nature of the membrane alcohol, the flow regime, the pH difference between the source and receiving phases and the number of operating cycles. The conversion results are in all cases better for nD than nDD. The counter-current flow regime is superior to the co-current flow. Increasing the pH difference between the source and receiving phases amplifies the process. The number of operating cycles is limited to five, after which the regeneration of the membrane dispersion is required. The apparent catalytic rate constant (kapp) of the new catalytic material based on the emulsion membrane with the nanodispersion of osmium nanoparticles (0.1 × 10-3 s-1 for n-dodecanol and 0.9 × 10-3 s-1 for n-decanol) is lower by an order of magnitude compared to those based on adsorption on catalysts from the platinum metal group. The advantage of the tested membrane catalytic material is that it extracts p-aminophenol in the acid-receiving phase.

6.
J Funct Biomater ; 14(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38132814

RESUMO

The current study reports the use of silver (Ag) and samarium (Sm) as dopants to improve the properties of standard bioglass in terms of biological performance. This experiment considers thin films of doped bioglass obtained by pulsed laser deposition (PLD) and spin coating (SC). For both methods, some parameters were gradually varied, as the main objective was to produce a bioglass that could be used in biomedical fields. In order to study the morphology, the phase composition and other properties, the samples obtained were subjected to multiple analyses, such as thermal analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared (FT-IR), Raman spectroscopy, and x-ray diffraction (XRD). Furthermore, the in vitro bioactivity of the samples, as assessed through simulated body fluid (SBF) immersion, as well as immunocytochemistry and evaluation of actin filaments, assessed through fluorescence microscopy, are reported. The results confirmed the formation of the designed vitreous target employed as the source of material in the PLD experiments only at sintering temperatures below 800 °C; this vitreous nature was preserved in the grown film as well. The presence of Ag and Ce dopants in the parent glassy matrix was validated for all stages, from powder, to target, to PLD/SC-derived coatings. Additionally, it was demonstrated that the surface topography of the layers can be adjusted by using substrates with different roughness or by modulating the processing parameters, such as substrate temperature and working pressure in PLD, rotation speed, and number of layers in SC. The developed material was found to be highly bioactive after 28 days of immersion in SBF, but it was also found to be a potential candidate for inhibiting the growth of Gram-negative bacteria and a suitable support for cell growth and proliferation.

7.
Nanomaterials (Basel) ; 13(22)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-37999328

RESUMO

A novel high-entropy perovskite powder with the composition Bi0.2K0.2Ba0.2Sr0.2Ca0.2TiO3 was successfully synthesized using a modified Pechini method. The precursor powder underwent characterization through Fourier Transform Infrared Spectroscopy and thermal analysis. The resultant Bi0.2K0.2Ba0.2Sr0.2Ca0.2TiO3 powder, obtained post-calcination at 900 °C, was further examined using a variety of techniques including X-ray diffraction, Raman spectroscopy, X-ray fluorescence, scanning electron microscopy, and transmission electron microscopy. Ceramic samples were fabricated by conventional sintering at various temperatures (900, 950, and 1000 °C). The structure, microstructure, and dielectric properties of these ceramics were subsequently analyzed and discussed. The ceramics exhibited a two-phase composition comprising cubic and tetragonal perovskites. The grain size was observed to increase from 35 to 50 nm, contingent on the sintering temperature. All ceramic samples demonstrated relaxor behavior with a dielectric maximum that became more flattened and shifted towards lower temperatures as the grain size decreased.

8.
Nanomaterials (Basel) ; 13(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37887945

RESUMO

Magnetite nanoparticles (Fe3O4 NPs) are among the most investigated nanomaterials, being recognized for their biocompatibility, versatility, and strong magnetic properties. Given that their applicability depends on their dimensions, crystal morphology, and surface chemistry, Fe3O4 NPs must be synthesized in a controlled, simple, and reproducible manner. Since conventional methods often lack tight control over reaction parameters and produce materials with unreliable characteristics, increased scientific interest has been directed to microfluidic techniques. In this context, the present paper describes the development of an innovative 3D microfluidic platform suitable for synthesizing uniform Fe3O4 NPs with fine-tuned properties. On-chip co-precipitation was performed, followed by microwave-assisted silanization. The obtained nanoparticles were characterized from the compositional and microstructural perspectives by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Moreover, supplementary physicochemical investigations, such as Fourier Transform Infrared Spectroscopy (FT-IR), Kaiser Test, Ultraviolet-Visible (UV-Vis) Spectrophotometry, Dynamic Light Scattering (DLS), and Thermogravimetry and Differential Scanning Calorimetry (TG-DSC) analyses, demonstrated the successful surface modification. Considering the positive results, the presented synthesis and functionalization method represents a fast, reliable, and effective alternative for producing tailored magnetic nanoparticles.

9.
Pharmaceutics ; 15(10)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37896230

RESUMO

One major problem with the overuse of antibiotics is that the microorganisms acquire resistance; thus the dose must be increased unsustainably. To overcome this problem, researchers from around the world are actively investigating new types of antimicrobials. Zinc oxide (ZnO) nanoparticles (NPs) have been proven to exhibit strong antimicrobial effects; moreover, the Food and Drugs Administration (FDA) considers ZnO as GRAS (generally recognized as safe). Many essential oils have antimicrobial activity and their components do not generate resistance over time. One of the drawbacks is the high volatility of some components, which diminishes the antimicrobial action as they are eliminated. The combination of ZnO NPs and essential oils can synergistically produce a stronger antimicrobial effect, and some of the volatile compounds can be retained on the nanoparticles' surface, ensuring a better-lasting antimicrobial effect. The samples were characterized with X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), and thermal analysis (TG-DSC) coupled with analysis of evolved gases using FTIR. The ZnO NPs, with a size of ~35 nm, exhibited a loading between 1.44% and 15.62%-the lower values were specific for limonene-containing oils (e.g., orange, grapefruit, bergamot, or limette), while high values were obtained from cinnamon, minzol, thyme, citronella, and lavender oils-highlighting differences among non-polar terpenes and alcohol or aldehyde derivatives. The antibacterial assay indicated the existence of a synergic action among components and a high dependency on the percentage of loaded oil. Loaded nanoparticles offer immense potential for the development of materials with specific applications, such as wound dressings or food packaging. These nanoparticles can be utilized in scenarios where burst delivery is desired or when prolonged antibacterial activity is sought.

10.
Pharmaceutics ; 15(9)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37765184

RESUMO

Magnetite nanoparticles (MNPs) have been intensively studied for biomedical applications, especially as drug delivery systems for the treatment of infections. Additionally, they are characterized by intrinsic antimicrobial properties owing to their capacity to disrupt or penetrate the microbial cell wall and induce cell death. However, the current focus has shifted towards increasing the control of the synthesis reaction to ensure more uniform nanoparticle sizes and shapes. In this context, microfluidics has emerged as a potential candidate method for the controlled synthesis of nanoparticles. Thus, the aim of the present study was to obtain a series of antibiotic-loaded MNPs through a microfluidic device. The structural properties of the nanoparticles were investigated through X-ray diffraction (XRD) and, selected area electron diffraction (SAED), the morphology was evaluated through transmission electron microscopy (TEM) and high-resolution TEM (HR-TEM), the antibiotic loading was assessed through Fourier-transform infrared spectroscopy (FT-IR) and, and thermogravimetry and differential scanning calorimetry (TG-DSC) analyses, and. the release profiles of both antibiotics was determined through UV-Vis spectroscopy. The biocompatibility of the nanoparticles was assessed through the MTT assay on a BJ cell line, while the antimicrobial properties were investigated against the S. aureus, P. aeruginosa, and C. albicans strains. Results proved considerable uniformity of the antibiotic-containing nanoparticles, good biocompatibility, and promising antimicrobial activity. Therefore, this study represents a step forward towards the microfluidic development of highly effective nanostructured systems for antimicrobial therapies.

11.
Pharmaceutics ; 15(7)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37514068

RESUMO

We report on a comparative in vitro study of selective cytotoxicity against MCF7 tumor cells and normal VERO cells tested on silver-based nanocoatings synthesized by the matrix-assisted pulsed laser evaporation (MAPLE) technique. Silver nanoparticles (AgNPs) were loaded with five representative cytostatic drugs (i.e., doxorubicin, fludarabine, paclitaxel, gemcitabine, and carboplatin) and with five essential oils (EOs) (i.e., oregano, rosemary, ginger, basil, and thyme). The as-obtained coatings were characterized by X-ray diffraction, thermogravimetry coupled with differential scanning calorimetry, Fourier-transform IR spectroscopy, IR mapping, and scanning electron microscopy. A screening of the impact of the prepared nanocoatings on the MCF7 tumor and normal VERO cell lines was achieved by means of cell viability MTT and cytotoxicity LDH assays. While all nanocoatings loaded with antitumor drugs exhibited powerful cytotoxic activity against both the tumor and the normal cells, those embedded with AgNPs loaded with rosemary and thyme EOs showed remarkable and statistically significant selective cytotoxicity against the tested cancercells. The EO-loaded nanocoatings were tested for antimicrobial and antibiofilm activity against Staphylococcus aureus, Escherichia coli, and Candida albicans. For all studied pathogens, the cell viability, assessed by counting the colony-forming units after 2 and 24 h, was significantly decreased by all EO-based nanocoatings, while the best antibiofilm activity was evidenced by the nanocoatings containing ginger and thyme EOs.

12.
Molecules ; 28(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446861

RESUMO

Since cancer is a continuously increasing concern for the general population, more efficient treatment alternatives ought to be developed. In this regard, a promising direction is represented by the use of magnetite nanoparticles (MNPs) to act both as a nanocarrier for the targeted release of antitumoral drugs and as hyperthermia agents. Thus, the present study focused on improving the control upon the outcome properties of MNPs by using two synthesis methods, namely the co-precipitation and microwave-assisted hydrothermal method, for the incorporation of usnic acid (UA), a natural lichen-derived metabolite with proven anticancer activity. The obtained UA-loaded MNPs were thoroughly characterized regarding their morpho-structural and physicochemical properties through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS) and zeta potential, scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM). Results demonstrated the formation of magnetite as the unique mineralogical phase through both types of synthesis, with increased uniformity regarding the drug loading efficiency, size, stability, and magnetic properties obtained through the microwave-assisted hydrothermal method. Furthermore, the cytotoxicity of the nanostructures against the HEK 293T cell line was investigated through the XTT assay, which further proved their potential for anticancer treatment applications.


Assuntos
Nanopartículas de Magnetita , Neoplasias , Humanos , Nanopartículas de Magnetita/química , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura , Difração de Raios X
13.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37511219

RESUMO

The recognized antimicrobial activity of silver nanoparticles is a well-studied property, especially when designing and developing biomaterials with medical applications. As biological activity is closely related to the physicochemical characteristics of a material, aspects such as particle morphology and dimension should be considered. Microfluidic systems in continuous flow represent a promising method to control the size, shape, and size distribution of synthesized nanoparticles. Moreover, using microfluidics widens the synthesis options by creating and controlling parameters that are otherwise difficult to maintain in conventional batch procedures. This study used a microfluidic platform with a cross-shape design as an innovative method for synthesizing silver nanoparticles and varied the precursor concentration and the purging speed as experimental parameters. The compositional and microstructural characterization of the obtained samples was carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and dynamic light scattering (DLS). Four formulations of alginate-based hydrogels with the addition of hyaluronic acid and silver nanoparticles were obtained to highlight the antimicrobial activity of silver nanoparticles and the efficiency of such a composite in wound treatment. The porous structure, swelling capacity, and biological properties were evaluated through physicochemical analysis (FT-IR and SEM) and through contact with prokaryotic and eukaryotic cells. The results of the physicochemical and biological investigations revealed desirable characteristics for performant wound dressings (i.e., biocompatibility, appropriate porous structure, swelling rate, and degradation rate, ability to inhibit biofilm formation, and cell growth stimulation capacity), and the obtained materials are thus recommended for treating chronic and infected wounds.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Ácido Hialurônico/química , Prata/farmacologia , Prata/química , Microfluídica , Espectroscopia de Infravermelho com Transformada de Fourier , Alginatos/química , Nanopartículas Metálicas/química , Anti-Infecciosos/farmacologia , Bandagens , Antibacterianos/farmacologia , Antibacterianos/química
14.
Pharmaceutics ; 15(6)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37376176

RESUMO

The production of highly porous and three-dimensional (3D) scaffolds with biomimicking abilities has gained extensive attention in recent years for tissue engineering (TE) applications. Considering the attractive and versatile biomedical functionality of silica (SiO2) nanomaterials, we propose herein the development and validation of SiO2-based 3D scaffolds for TE. This is the first report on the development of fibrous silica architectures, using tetraethyl orthosilicate (TEOS) and polyvinyl alcohol (PVA) during the self-assembly electrospinning (ES) processing (a layer of flat fibers must first be created in self-assembly electrospinning before fiber stacks can develop on the fiber mat). The compositional and microstructural characteristics of obtained fibrous materials were evaluated by complementary techniques, in both the pre-ES aging period and post-ES calcination. Then, in vivo evaluation confirmed their possible use as bioactive scaffolds in bone TE.

15.
Membranes (Basel) ; 13(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37367795

RESUMO

Since the water pollution problem still affects the environmental system and human health, the need to develop innovative membranes has become imperious. Lately, researchers have focused on developing novel materials to help diminish the contamination problem. The aim of present research was to obtain innovative adsorbent composite membranes based on a biodegradable polymer, alginate, to remove toxic pollutants. Of all pollutants, lead was chosen due to its high toxicity. The composite membranes were successfully obtained through a direct casting method. The silver nanoparticles (Ag NPs) and caffeic acid (CA) from the composite membranes were kept at low concentrations, which proved enough to bestow antimicrobial activity to the alginate membrane. The obtained composite membranes were characterised by Fourier transform infrared spectroscopy and microscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TG-DSC). Swelling behaviour, lead ion (Pb2+) removal capacity, regeneration and reusability were also determined. Further, the antimicrobial activity was tested against selected pathogenic strains (S. aureus, E. faecalis sp., P. aeruginosa, E. coli and C. albicans). The presence of Ag NPs and CA improves the antimicrobial activity of the newly developed membranes. Overall, the composite membranes are suitable for complex water treatment (removal of heavy metal ions and antimicrobial treatment).

16.
Polymers (Basel) ; 15(10)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37242827

RESUMO

In the present study, two chelating resins were prepared and used for simultaneous adsorption of toxic metal ions, i.e., Cr3+, Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, and Pb2+ (MX+). In the first step, chelating resins were prepared starting with styrene-divinylbenzene resin, a strong basic anion exchanger Amberlite IRA 402(Cl-) with two chelating agents, i.e., tartrazine (TAR) and amido black 10B (AB 10B). Key parameters such as contact time, pH, initial concentration, and stability were evaluated for the obtained chelating resins (IRA 402/TAR and IRA 402/AB 10B). The obtained chelating resins show excellent stability in 2M HCl, 2M NaOH, and also in ethanol (EtOH) medium. The stability of the chelating resins decreased when the combined mixture (2M HCl:EtOH = 2:1) was added. The above-mentioned aspect was more evident for IRA 402/TAR compared to IRA 402/AB 10B. Taking into account the higher stability of the IRA 402/TAR and IRA 402/AB 10B resins, in a second step, adsorption studies were carried out on complex acid effluents polluted with MX+. The adsorption of MX+ from an acidic aqueous medium on the chelating resins was evaluated using the ICP-MS method. The following affinity series under competitive analysis for IRA 402/TAR was obtained: Fe3+(44 µg/g) > Ni2+(39.8 µg/g) > Cd2+(34 µg/g) > Cr3+(33.2 µg/g) > Pb2+(32.7 µg/g) > Cu2+ (32.5 µg/g) > Mn2+(31 µg/g) > Co2+(29 µg/g) > Zn2+ (27.5 µg/g). While for IRA 402/AB 10B, the following behavior was observed: Fe3+(58 µg/g) > Ni2+(43.5 µg/g) > Cd2+(43 µg/g) > Cu2+(38 µg/g) > Cr3+(35 µg/g) > Pb2+(34.5 µg/g) > Co2+(32.8 µg/g) > Mn2+(33 µg/g) > Zn2+(32 µg/g), consistent with the decreasing affinity of MX+ for chelate resin. The chelating resins were characterized using TG, FTIR, and SEM analysis. The obtained results showed that the chelating resins prepared have promising potential for wastewater treatment in the context of the circular economy approach.

17.
Antioxidants (Basel) ; 12(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37107325

RESUMO

Lonicera caerulaea L. and Aronia melanocarpa (Michx.) Elliot fruits are frequently used for their health benefits as they are rich in bioactive compounds. They are recognized as a source of natural and valuable phytonutrients, which makes them a superfood. L. caerulea presents antioxidant activity three to five times higher than other berries which are more commonly consumed, such as blackberries or strawberries. In addition, their ascorbic acid level is the highest among fruits. The species A. melanocarpa is considered one of the richest known sources of antioxidants, surpassing currants, cranberries, blueberries, elderberries, and gooseberries, and contains one of the highest amounts of sorbitol. The non-edible leaves of genus Aronia became more extensively analyzed as a byproduct or waste material due to their high polyphenol, flavonoid, and phenolic acid content, along with a small amount of anthocyanins, which are used as ingredients in nutraceuticals, herbal teas, bio-cosmetics, cosmeceuticals, food and by the pharmaceutical industry. These plants are a rich source of vitamins, tocopherols, folic acid, and carotenoids. However, they remain outside of mainstream fruit consumption, being well known only to a small audience. This review aims to shed light on L. caerulaea and A. melanocarpa and their bioactive compounds as healthy superfoods with antioxidant, anti-inflammatory, antitumor, antimicrobial, and anti-diabetic effects, and hepato-, cardio-, and neuro-protective potential. In this view, we hope to promote their cultivation and processing, increase their commercial availability, and also highlight the ability of these species to be used as potential nutraceutical sources, helpful for human health.

18.
Gels ; 9(4)2023 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-37102906

RESUMO

The aim of the present study was to obtain a hydrogel-based film as a carrier for the sustained and controlled release of vancomycin, an antibiotic commonly used in various types of infections. Considering the high-water solubility of vancomycin (>50 mg/mL) and the aqueous medium underlying the exudates, a prolonged release of vancomycin from an MCM-41 carrier was sought. The present work focused on the synthesis of malic acid coated magnetite (Fe3O4/malic) by co-precipitation, synthesis of MCM-41 by a sol-gel method and loading of MCM-41 with vancomycin, and their use in alginate films for wound dressing. The nanoparticles obtained were physically mixed and embedded in the alginate gel. Prior to incorporation, the nanoparticles were characterized by XRD, FT-IR and FT-Raman spectroscopy, TGA-DSC and DLS. The films were prepared by a simple casting method and were further cross-linked and examined for possible heterogeneities by means of FT-IR microscopy and SEM. The degree of swelling and the water vapor transmission rate were determined, considering their potential use as wound dressings. The obtained films show morpho-structural homogeneity, sustained release over 48 h and a strong synergistic enhancement of the antimicrobial activity as a consequence of the hybrid nature of these films. The antimicrobial efficacy was tested against S. aureus, two strains of E. faecalis (including vancomycin-resistant Enterococcus, VRE) and C. albicans. The incorporation of magnetite was also considered as an external triggering component in case the films were used as a magneto-responsive smart dressing to stimulate vancomycin diffusion.

19.
Membranes (Basel) ; 13(3)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36984671

RESUMO

Melatonin is the hormone that focuses the attention of the researchers in the medical, pharmaceutical, materials, and membranes fields due to its multiple biomedical implications. The variety of techniques and methods for the controlled release of melatonin is linked to the multitude of applications, among which sports medicine occupies a special place. This paper presents the preparation and characterization of composite membranes based on chitosan (Chi) and sulfonated ethylene-propylene-diene terpolymer (sEPDM). The membranes were obtained by controlled vacuum evaporation from an 8% sEPDM solution in toluene (w/w), in which chitosan was dispersed in an ultrasonic field (sEPDM:Chi = 1:1, w/w). For the comparative evaluation of the membranes' performances, a melatonin-chitosan-sulfonated ethylene-propylene-diene terpolymer (Mel:Chi:sEPDM = 0.5:0.5:1.0, w/w/w) test membrane was made. The prepared membranes were morphologically and structurally characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersive spectroscopy analysis (EDAX), thermal analysis (TG, DSC), thermal analysis coupled with chromatography and infrared analysis, and contact angle measurements, but also from the point of view of performance in the process of transport and release of melatonin in dedicated environments (aqueous solutions with controlled pH and salinity). The prepared membranes can release melatonin in amounts between 0.4 mg/cm2·per day (sEPDM), 1.6 mg/ cm2·per day (Chi/sEPDM), and 1.25 mg/cm2·per day (Mel/Chi/SEPDM).

20.
Membranes (Basel) ; 13(3)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36984736

RESUMO

This paper presents the preparation and characterization of composite membranes based on chitosan (Chi), sulfonated ethylene-propylene-diene terpolymer (sEPDM), and polypropylene (PPy), and designed to capture hydrogen sulfide. The Chi/sEPDM/PPy composite membranes were prepared through controlled evaporation of a toluene dispersion layer of Chi:sEPDM 1;1, w/w, deposited by immersion and under a slight vacuum (100 mmHg) on a PPy hollow fiber support. The composite membranes were characterized morphologically, structurally, and thermally, but also from the point of view of their performance in the process of hydrogen sulfide sequestration in an acidic media solution with metallic ion content (Cu2+, Cd2+, Pb2+, and/or Zn2+). The operational parameters of the pertraction were the pH, pM, matrix gas flow rate, and composition. The results of pertraction from synthetic gases mixture (nitrogen, methane, carbon dioxide) indicated an efficient removal of hydrogen sulfide through the prepared composite membranes, as well as its immobilization as sulfides. The sequestration and the recuperative separation, as sulfides from an acid medium, of the hydrogen sulfide reached up to 96%, decreasing in the order: CuS > PbS > CdS > ZnS.

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